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Cats Or No Cats

lilbutler2@hotmail.com

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Krambo Enthusiast

Krambo

Posted
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Personally, I would gut the cats in your case. Exhaust tone will change but too extreme. Be sure to modify your tune file to delete the rear O2 DTC's (for offroad only of course!) and to dial in your fueling.

GMstrong Enthusiast

GMstrong

Posted
Posted

Honestly if you dont need them delete them.Also if you dont have these already get some LTs and a good catback but i hate catbacks i always loved the sound and rumble from a dumped exhaust.I have true dual glasspacks dumped on my 9c1 Sounds great from idle-redline and a craaaazzzyy ass sound when i go under a over pass.

stlavsa Senior Enthusiast

stlavsa

Posted
Posted

Whats a "built motor" and how much PSI are you running? I would imagine that even at a lower boost level the cats are holding you back a little. Personally I wouldnt "gut" the cats. Thats a good way to end up with a raspy, nasty sounding exhaust note.

 

Rather I would replace the cats with straight pipes, keeping the transitions the same size as the exhaust is going to not only help with sound but with exhaust evacuation as well.

lilbutler2@hotmail.com Enthusiast

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1213646[/url]']

Whats a "built motor" and how much PSI are you running? I would imagine that even at a lower boost level the cats are holding you back a little. Personally I wouldnt "gut" the cats. Thats a good way to end up with a raspy, nasty sounding exhaust note.

 

Rather I would replace the cats with straight pipes, keeping the transitions the same size as the exhaust is going to not only help with sound but with exhaust evacuation as well.

 

Its an aluminum block fully forged internals,mild cam, oilers, everything built by Katech performance. The supercharger is pushing 9-10lbs. And that's what I was thinking is replace them with straight pipe that way I'll still have cats if I ever need them.

stlavsa Senior Enthusiast

stlavsa

Posted
Posted
1213646[/url]']

Whats a "built motor" and how much PSI are you running? I would imagine that even at a lower boost level the cats are holding you back a little. Personally I wouldnt "gut" the cats. Thats a good way to end up with a raspy, nasty sounding exhaust note.

 

Rather I would replace the cats with straight pipes, keeping the transitions the same size as the exhaust is going to not only help with sound but with exhaust evacuation as well.

 

Its an aluminum block fully forged internals,mild cam, oilers, everything built by Katech performance. The supercharger is pushing 9-10lbs. And that's what I was thinking is replace them with straight pipe that way I'll still have cats if I ever need them.

 

 

ya u should do it. You will need to make sure the secondary O2s are disabled in your tune.

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